西藏“一江两河”中部流域地区土地沙漠化的成因与发展趋势

西藏“一江两河”中部流域地区是西藏自治区重要的开发和建设区，但区内沙漠化的迅速发展对其社会经济发展造成了重大危害并构成严重威胁，亟待对本区的沙漠化问题予以充分研究，通过对该区沙漠化自然因素，人为因素及其相互关系的分析，探讨了其沙漠化的成因与发展趋势，认为本区的沙漠化是缓慢的自然沙漠化过程为基础，自然与人为因子共同作用所形成的人为加速与加剧过程，是人类不合理的，强度的土地利用与脆弱的生态环境，贫乏的

STUDY ON THE CAUSE AND DEVELOPMENT TREND OF DESERTIFICATION IN THE MIDSTREAM REGION OF YARLUNG ZANGBO RIVER,TIBET

The midstream region of Yarlung Zangbo River is an important development andconstruction region in Tibet in recent years.but the fast development of desertification has causedimmense damages to its social and economic development,so the study on desertification in this regionis significant.This paper studies the causes and development trend of desertification in this regionthrough analysis of natural and human factors as well as their relationship. It can be concluded thatthe descrtification in the midstream region of the Yarlung Zangbo River is one process which isaccelerated and intensified by human activities thtough the mutual action of natural and human factotson the basis of the slow natural dcscrtification process.It is resulted from the dislocation of unrationaland intensive human activitiesand fragile ecologic envirtonmnt and meagre natural resources and tends to become more wide and severe.